There is often a need to introduce temporary beacon on runways in airports. For example, if a runway is being repaired, there is a need to signal to approaching pilots that the runway is unavailable for landing.
Currently, lime is used to write a sign resembling the letter “X” on such a runway. Therefore, a pilot erroneously approaching the closed runway sees the “X” and therefore can clear the runway.
However, lime is dissolved by rain, changes the PH of soil around the runways, and is toxic and therefore cumbersome to apply. In addition, it is very hard to completely remove a mark made with lime from a runway. Also, lime is not reusable. In addition to all these disadvantages, the visibility of lime on runways is only average both during the day and at night.
Another type of temporary beacon for runways consists in a mesh fence. However, such fences are somewhat difficult to see during the day and almost impossible to see at night, even when illuminated.
There are also several types of beacon or marking devices using artificial lighting sources for nighttime illumination as well as some using luminescent means including the use of high reflective material but they are generally setup upright and at the sides of the landing strips and are not used for indicating the closing of a landing strips but rather for more genreal and permanent markings and not for temporary markings that need to be installed or removed quickly.